This invention relates to a mobile, ecologically and environmentally friendly mud-gas containment system mounted upon a single, highway transportable skid. The mobile device receives, from drilling, production, and/or completion operations, both a waste gas and a volume of drilling mud having entrained and commingled waste gas. The waste gas is communicated to a removable flare stack. The volume of the drilling mud, with entrained waste gas, is received at a containment vessel. This invention also relates to capturing and storing the drilling mud for recycling.
During well drilling, production, and/or completion operations, numerous operational activities and components function simultaneously. Drilling fluid, also called “mud,” is used for the lubrication, cooling, and removal of the cuttings from the well during the drilling, production, and/or completion operations. Because the mud is used within the well, waste gas from the well becomes entrained and commingled within the mud, creating a mud-gas mixture. During drilling operations, safely separating the gas from the mud-gas mixture usually requires communicating the mud-gas mixture to a mud-gas separator. Subsequently, substantially gas-free mud passes to a holding tank or reserve pit for recycling at a later date. Simultaneously, the released waste gas is burned at a flare stack.
In the event of a well blow out or other emergency, the mud-gas mixture from a wellbore is rapidly dumped into the holding tank or reserve pit. Unfortunately, the gradual out-gassing of waste gas from the mud mixture creates a combustion hazard near the well site. Capture and safe disposal of the waste gas is limited or non-existent for such situations.
When employing a standard mud-gas separator, a vent line communicates the waste gas away from the well site, or a mud-gas separator, to the flare stack. Unfortunately, currently available mud-gas separators frequently pass some mud with the gas through the vent line with the waste gas. Over time, the mud residue within the vent line begins to impede and eventually block the flow of waste gas to the flare stack. The usual method to remove the mud residue is to disassemble the vent line and flush the residue out.
Environmental concerns and technology improvements have dictated that waste products be captured at the well site while presenting a smaller footprint for well drilling operations. Thus, it is important to design the components for well operations to be carried on transportation skids. Well operations typically include well drilling, production, and/or completion operations. The mobility helps prevent any by-products of the process from contaminating the area. Numerous transportation skids are required to carry all of the well site support equipment used to capture waste products. To reduce the number of skids at a well site, a single skid carrying all the components of an ecological friendly mud-gas containment system is desired. The skid-based ecological mud-gas containment system should provide for: safe flaring of waste gas; environmentally safe removal of the mud residue build-up in a flare stack vent line; emergency dumping of the mud-gas mixture from a well with continued waste gas separation from the mud-gas mixture; and recovery of the mud for recycling. The present invention solves the foregoing problems by providing an environmentally/ecologically friendly mobile mud-gas containment system.